We are surveying pyrenomycetous fungi for biologically active compounds. Isolates of the fungi are grown on a variety of media, under different conditions of culture to find the optimum conditions for the production of specific compounds. Activity against several bacteria and fungi are tested. When the growth of the tester bacterium or fungus is inhibited, the active principle is isolated and characterized. When the active principle is a new compound, we endeavor to elucidate its structure. Compounds not previously tested for antitumor activity are sent to N.I.H. BIBLIOGRAPHIC REFERENCES: Carey,S.T. and C.T. Rogerson. 1976. Taxonomy and morphology of a new species of Hypocrea on Marasmius. Brittonia 28: 381-389. Nair, M.S.R. and S.T. Carey. 1977. Metabolites of Pyrenomycetes VII. Structure of sibirinone. Phytochemistry 16, in press.